Description:
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I wonder if we could add features to xhprof , that would be activated with a special flag in xhprof_enable()) such as :

- Record file and line number from which function calls are made
- Record args type functions (and returns)

I know that xdebug already has these features, but xdebug is very slow (+40% when all features disabled), whereas xhprof has no impact when it isn't launched (this is what I'm looking for).

I don't know whether these informations are available in an extension or not, compared to a zend_extension (such as xdebug).